Heat-resistant insulating substrate, thermal printing head, and thermographic apparatus

Abstract

A layer of an amorphous substance containing at least one member from among hydrogen and halogen elements and using as main components thereof silicon and at least one member selected from among nitrogen, carbon, and oxygen is formed as a resin-protecting layer or an abrasion-resistant layer in a thermal printing head or as a resin-protecting layer in a heat-resistant insulating substrate. The hardness of the substrate itself is greatly improved by this layer of the amorphous substance. As the result, the substrate as a whole or the thermal printing head as a whole acquires high rigidity and improved resistance to crack.

What is claimed is: 
     
       1. A heat-resistant insulating substrate, comprising at least a highly thermoconductive supporting substrate, a heat-resistant resin layer formed on the supporting substrate, and a resin-protecting layer deposited on the heat-resistant resin layer and formed of one layer, or a plurality of layers, of an amorphous substance containing at least one member from selected hydrogen and halogen elements and using as main components thereof silicon and at least one member selected from nitrogen, carbon, and oxygen. 
     
     
       2. A heat-resistant insulating substrate according to claim 1, wherein the heat-resistant resin layer is a resin layer using polyimide or polyamideimide as a main component thereof. 
     
     
       3. A heat-resistant insulating substrate according to claim 1 or claim 2, wherein the resin-protecting layer is formed so as to deposit an amorphous substance containing silicon, at least one element selected from the group of hydrogen and halogen, and at least one element selected from the group of nitrogen, carbon, and oxygen using a plasma CVD method, the method including the process of glow discharging so as to convert gases into a plasma and deposit a thin film on the heat-resistant layer.